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Full-Text Articles in Law

Law Library Blog (January 2021): Legal Beagle's Blog Archive, Roger Williams University School Of Law Jan 2021

Law Library Blog (January 2021): Legal Beagle's Blog Archive, Roger Williams University School Of Law

Law Library Newsletters/Blog

No abstract provided.


Power And Statistical Significance In Securities Fraud Litigation, Jill E. Fisch, Jonah B. Gelbach Feb 2020

Power And Statistical Significance In Securities Fraud Litigation, Jill E. Fisch, Jonah B. Gelbach

Faculty Scholarship at Penn Law

Event studies, a half-century-old approach to measuring the effect of events on stock prices, are now ubiquitous in securities fraud litigation. In determining whether the event study demonstrates a price effect, expert witnesses typically base their conclusion on whether the results are statistically significant at the 95% confidence level, a threshold that is drawn from the academic literature. As a positive matter, this represents a disconnect with legal standards of proof. As a normative matter, it may reduce enforcement of fraud claims because litigation event studies typically involve quite low statistical power even for large-scale frauds.

This paper, written for ...


The Logic And Limits Of Event Studies In Securities Fraud Litigation, Jill E. Fisch, Jonah B. Gelbach, Jonathan Klick Jan 2018

The Logic And Limits Of Event Studies In Securities Fraud Litigation, Jill E. Fisch, Jonah B. Gelbach, Jonathan Klick

Faculty Scholarship at Penn Law

Event studies have become increasingly important in securities fraud litigation after the Supreme Court’s decision in Halliburton II. Litigants have used event study methodology, which empirically analyzes the relationship between the disclosure of corporate information and the issuer’s stock price, to provide evidence in the evaluation of key elements of federal securities fraud, including materiality, reliance, causation, and damages. As the use of event studies grows and they increasingly serve a gatekeeping function in determining whether litigation will proceed beyond a preliminary stage, it will be critical for courts to use them correctly.

This Article explores an array ...


Expert Mining And Required Disclosure, Jonah B. Gelbach Jan 2014

Expert Mining And Required Disclosure, Jonah B. Gelbach

Faculty Scholarship at Penn Law

No abstract provided.


If The Shoe Fits They Might Acquit: The Value Of Forensic Science Testimony, Jonathan Koehler Jan 2011

If The Shoe Fits They Might Acquit: The Value Of Forensic Science Testimony, Jonathan Koehler

Faculty Working Papers

The probative value of forensic science evidence (such as a shoeprint) varies widely depending on how the evidence and hypothesis of interest is characterized. This paper uses a likelihood ratio (LR) approach to identify the probative value of forensic science evidence. It argues that the "evidence" component should be characterized as a "reported match," and that the hypothesis component should be characterized as "the matching person or object is the source of the crime scene sample." This characterization of the LR forces examiners to incorporate risks from sample mix-ups and examiner error into their match statistics. But how will legal ...


Law, Statistics, And The Reference Class Problem, Edward K. Cheng Jan 2009

Law, Statistics, And The Reference Class Problem, Edward K. Cheng

Vanderbilt Law School Faculty Publications

Statistical data are powerful, if not crucial, pieces of evidence in the courtroom. Whether one is trying to demonstrate the rarity of a DNA profile, estimate the value of damaged property, or determine the likelihood that a criminal defendant will recidivate, statistics often have an important role to play. Statistics, however, raise a number of serious challenges for the legal system, including concerns that they are difficult to understand, are given too much deference from juries, or are easily manipulated by the parties' experts. In this preview piece, I address one of these challenges, known as the "reference class problem ...


Wrongly Accused Redux: How Race Contributes To Convicting The Innocent: The Informants Example, Andrew E. Taslitz Jan 2008

Wrongly Accused Redux: How Race Contributes To Convicting The Innocent: The Informants Example, Andrew E. Taslitz

School of Law Faculty Publications

This article analyzes five forces that may raise the risk of convicting the innocent based upon the suspect's race: the selection, ratchet, procedural justice, bystanders, and aggressive-suspicion effects. In other words, subconscious forces press police to focus more attention on racial minorites, the ratchet makes this focus every-increasing, the resulting sense by the community of unfair treatment raises its involvment in crime while lowering its willingness to aid the police in resisting crime, innocent persons suffer when their skin color becomes associated with criminality, and the police use more aggressive techniques on racial minorities in a way that raises ...